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Report to the Senate Appropriations Committee on 

The Radiogenicity of Specific Cancers 

Under the Energy Employees Occupational Illness 

Compensation Program Act of 2000 as Amended 

National Institute for Occupational Safety and Health 

June, 2007
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SUMMARY 

In response to Senate Report (S. Rep.) 109-103 (2005), NIOSH examined the evidence for the 

radiogenicity1 of 11 “non-presumptive cancers” which were not included in the list of 22 

“specified cancers” referenced in the Energy Employees Occupational Illness Compensation 

Program Act of 2000 as amended (EEOICPA)2

. Based on a review of relevant scientific 

publications, NIOSH finds consistent evidence to support the radiogenicity of basal cell 

carcinoma. As requested in Senate Report 109-103, this report enumerates cases of basal cell 

carcinoma among classes of employees included in the Special Exposure Cohort (SEC). This is 

an interim report to Congress because it is expected that soon the United Nations Scientific 

Committee on the Effects of Atomic Radiation (UNSCEAR) will issue a new report 

summarizing comprehensive reviews of latest scientific findings. Based on examination of the 

findings from the new UNSCEAR study and other relevant information, NIOSH will issue a 

final report to Congress. 

RADIOGENICITY OF SPECIFIC CANCERS 

Comprehensive reviews of the radiogenicity of various specific cancers appeared in the peerreviewed scientific literature in the mid- and late 1990s (Boice et al. 1996, Mettler and Upton 

1995, Ron 1998). The most extensive recent examination of this topic was published by 

UNSCEAR (2000). These four reviews reflect the weight of the available scientific evidence 

 

1

 Radiogenicity refers to the causation of cancer in a given organ by exposure of that organ to ionizing radiation. 

2 The Department of Labor treats colon and rectal cancer as one type of cancer for purposes of EEOICPA, based on 

a National Cancer Institute advisory. 
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and are less prone than individual epidemiologic studies to reaching conclusions based on chance 

associations. 

The current classification under EEOICPA for site-specific cancers is found in Table 1. 

The table presents cancers in specific organs individually, including those that are grouped in the 

NIOSH Interactive Radioepidemiology Program (NIOSH-IREP) as “other respiratory,” “other 

endocrine,” and “other and ill defined sites.” 

Table 2 summarizes the primary conclusions of the four comprehensive reviews regarding the 

radiogenicity of each current non-presumptive site-specific cancer listed in Table 1. The four 

reviews differed in the list of cancers explicitly considered. To the extent that specific cancers 

were discussed, the authors were similar in concluding that little or no evidence of radiogenicity 

exists for chronic lymphocytic leukemia (CLL) and cancers of the connective tissue, larynx, 

lymphoma (Hodgkin’s), male genitalia, oral cavity, prostate, and uterus. 

The scientific evidence for skin cancer is more complicated, depending on the specific type of 

skin cancer. UNSCEAR (2000) recognized a strong relationship between radiation and basal cell 

carcinoma, but reported little evidence of an association for squamous cell carcinoma or 

malignant melanoma. 

In a study focused on the Japanese atomic bomb survivors, Ron et al. (1998) reached conclusions 

similar to those of UNSCEAR. In this study, there was a pronounced decrease in the excess 
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relative risk (ERR)per Sievert (ERR/Sv) for BCC as age increased, however, the risk remained 

significant at the 90% confidence interval for those who were exposed up to 39 years of age. 

Shore (2001) also examined the evidence of an association between skin cancer and ionizing 

radiation exposure, and his conclusions are consistent with those of Ron et al. (1998) and 

UNSCEAR (2000). In addition to the Japanese life span study, Shore reviewed other studies 

which provide evidence that BCC is related to exposure to ionizing radiation. These include 

evaluations of radiologists, uranium miners, and patients exposed during medical treatments. 

Shore (2001) concludes that: 

The principal epidemiological studies of ionizing radiation and skin cancer have all 

shown that radiation causes basal cell carcinoma but have not found dose-related 

excesses of squamous cell carcinoma or malignant melanoma. 

A summary of the findings of the studies reviewed by Shore is provided in Table 3. 

In contrast to these findings, a recent review argued for an association between radiation and 

malignant melanoma (Fink and Bates 2005). This review employed meta-analytical techniques 

to examine melanoma risks relative to leukemia risks in populations which may have been 

exposed to ionizing radiation. The report concluded that: 

 people exposed to ionizing radiation may be at increased risk of developing melanoma, 

although alternative explanations are possible. Future epidemiological studies of 

ionizing radiation effects should include melanoma as an outcome of interest. 
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Both Mettler and Upton (1995) and Boice et al. (1996) discussed skin cancer as a single entity, 

with the former indicating that a number of studies show an association with radiation, and the 

latter concluding that skin cancer is rarely associated with radiation and effects may be limited to 

high doses. Ron (1998) also considered skin cancers as a group and concluded that associations 

have been reported but are not well quantified. 

More recently, the United States National Academy of Sciences published Health Risks from 

Exposure to Low Levels of Ionizing Radiation: BEIR VII Phase 2 (National Research Council 

2006), which does not explicitly discuss the evidence of radiogenicity for specific cancers, but 

notes that nonmelanoma skin cancer has been linked clearly with radiation exposure in atomic 

bomb survivor data. 

Taken together, NIOSH finds consistent evidence to support the radiogenicity of basal cell 

carcinoma, but not malignant melanoma. As previously noted, the evidence of radiogenicity of 

basal cell carcinoma is much stronger for exposures received at young ages, particularly during 

childhood. The strength of the association declines with age, becoming statistically insignificant 

among most populations exposed at older ages (UNSCEAR 2000). Additionally, it is recognized 

that a primary cause of basal cell carcinoma is exposure to ultraviolet radiation in sunlight 

(UNSCEAR 2000). The nature and magnitude of the interaction between ultraviolet and 

ionizing radiation exposure are unknown at this time (Shore 2001, UNSCEAR 2000). 
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CONCLUSION 

Review of the evidence of radiogenicity of specific cancers indicates that there is strong 

epidemiologic evidence for the radiogenicity of basal cell carcinoma and insufficient evidence 

for larynx, CLL, lymphoma (Hodgkin’s), male genitalia, oral cavity, prostate, skin (squamous 

cell), uterus, and malignant melanoma. This interim report will be updated when UNSCEAR 

releases a new report. 

REFERENCES 

 1. Boice JJr, Land CE, and Preston DL. Ionizing radiation. In: Schottenfeld, D. and Fraumeni, 

J. F., Jr., eds. Cancer Epidemiology and Prevention. New York, NY: Oxford University 

Press; 1996: 319-354. 

 2. Fink CA and Bates MN. Melanoma and ionizing radiation: is there a causal relationship? 

Radiat.Res 164:701-710; 2005. 

 3. Mettler FAJr and Upton AC: Medical Effects of Ionizing Radiation. 2. Philadelphia, PA: 

W.B. Saunders Company; 1995. 

 4. National Research Council. Health risks from exposure to low levels of ionizing radiation 

(BEIR VII-Phase 2). Washington, DC: 2006. 

 5. Ron E. Ionizing radiation and cancer risk: evidence from epidemiology. Radiat.Res 

150:S30-S41; 1998. 

 6. Ron E, Preston DL, Kishikawa M, Kobuke T, Iseki M, Tokuoka S, Tokunaga M, and 

Mabuchi K. Skin tumor risk among atomic-bomb survivors in Japan. Cancer Causes 

Control 9:393-401; 1998. 

 7. Shore RE. Radiation-induced skin cancer in humans. Med.Pediatr.Oncol. 36:549-554; 

2001. 

 8. United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and 

effects of Ionizing radiation, UNSCEAR report to the General Assembly, Volume II: 

Effects. New York, NY: 2000. 
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Table 1: Current presumption status of specific cancers under EEOICPAa

Cancer Site Presumption Status 

Bile ducts Presumptive 

Bone Presumptive 

Brain Presumptive 

Breast Presumptive 

Colon/rectumb Presumptive 

Connective tissue Non-presumptive 

Esophagus Presumptive 

Gall bladder Presumptive 

Kidney Presumptive 

Larynx Non-presumptive 

Leukemia (exc. CLL) Presumptive 

Liver Presumptivec 

Lung Presumptive 

Lymphoma (NHL) Presumptive 

Lymphoma (Hodgkin’s) Non-presumptive 

Male genitalia Non-presumptive 

Multiple myeloma Presumptive 

Oral cavity Non-presumptive 

Ovary Presumptive 

Pancreas Presumptive 

Pharynx Presumptive 

Prostate Non-presumptive 

Salivary gland Presumptive 

Skin – BCC Non-presumptive 

Skin – SCC Non-presumptive 

Skin – melanoma Non-presumptive 

Small intestine Presumptive 

Stomach Presumptive 

Thyroid Presumptive 

Urinary bladder Presumptive 

Uterus Non-presumptive 

CLL = chronic lymphocytic leukemia 

NHL = non-Hodgkin’s lymphoma 

BCC = basal cell carcinoma 

SCC = squamous cell carcinoma 

a: To qualify as presumptive under the SEC, most cancers require a minimum time period of 5 

years between first exposure to radiation and cancer diagnosis. The exceptions are bone, 

lung, and kidney cancer (no minimum) and leukemia (minimum = 2 years). 

b: The Department of Labor’s Employment Standards Administration (ESA) noted that the 

National Cancer Institute considers rectal cancer to be the same as colon cancer based on 

tissue similarity, and thus groups the two together as colon/rectal cancer. Therefore rectal 

cancer is considered to be the same cancer as colon cancer for ESA purposes, and is treated 

as a specified cancer for EEOICPA purposes. 

c: Liver cancer is considered presumptive except when cirrhosis or hepatitis B is indicated. 
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Table 2: Evaluation of radiogenicity of currently nonpresumptive cancers in comprehensive reviews  (Mettler and Upton 1995) (Boice et al. 1996) (Ron 1998) (

Connective tissue NA Rarely associated with 

radiation with no reliable risk estimates available. Effect may be limited to high doses. 

NA 

Larynx “The oral cavity, pharynx and larynx 

are generally regarded as tissues of low risk in radiation carcinogenesis”. 

NA NA 

Lymphoma 

(Hodgkin’s) 

“With the exception of what are thought to be statistical chance associations radiation has not been associated with the development of Hodgkin’s disease”. 

Hodgkin’s never or sporadically associated with radiation with no risk estimate. Little evidence. 

“...rarely related to radiation exposure”. 

“...thindicabetweand raexternexpos

Male genitalia “The epidemiologic literature shows 

no causal association between male genital cancer and radiation exposure”. 

Never or sporadically associated with radiation with no risk estimates. Little or no evidence. 

“...rarely related to radiation exposure”. (testes) 

Oral cavity “Epidemiologic studies show no 

consistent or statistically significant increase in cancer of the oral cavity or pharynx following internal or external radiation exposure”. 

NA NA 

Prostate “A large number of epidemiologic 

studies have looked for an increased risk of prostate cancer after radiation exposure. At the present time there is no clear evidence that prostate cancer is induced by radiation”. 

Never or sporadically associated with radiation with no risk estimates. Little evidence. 

“...rarely related to radiation exposure”. 

“Data atomifrom providelevatcanceexpos

Skin - BCC “A number of studies indicate an 

association between skin cancer and 

Rarely associated with radiation with uncertain risk 

“Associations between radiation and cancer...have 

“Ionizinduc
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 (Mettler and Upton 1995) (Boice et al. 1996) (Ron 1998) (

radiation”. estimates. Effect may be 

limited to high doses. 

been reported, but the relationships are not as well quantified”. 

canceis almstrong basal-

Skin – SCC, 

malignant melanoma 

“A number of studies indicate an association between skin cancer and radiation”. 

Rarely associated with radiation with uncertain risk estimates. Effect may be limited to high doses. 

“Associations between radiation and cancer...have been reported, but the relationships are not as well quantified”. 

“To dlittle iassocionizimaligsquambut th

Uterus “The epidemiologic literature does 

not support radiation induction of uterine neoplasms”. 

Rarely associated with radiation with uncertain risk estimates. Effect may be limited to high doses. 

“...rarely related to radiation exposure”. (cervix) 

NA = this cancer was not explicitly considered BCC = basal cell carcinoma SCC = squamous cell carcinoma
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Table 3: Studies of Ionizing Radiation and Skin Cancer Risk (from Shore 2001) 

Study Relative Risk 

(at 1 Gray or Sievert) 

95% Confidence 

Interval 

Japanese atomic bomb 2.8 1.8-4.3 

Israel tinea capitas 1.7 1.3-2.4 

New York tinea capitas X-ray 1.6 1.3-2.0 

Enlarged thymus X-ray 2.1 1.4-3.0 

Lymphoid tissue X-ray 1.2 1.1-1.7 

Enlarged tonsils X-ray 1.1 1.0-1.2 

Uranium miners 2.1 1.7-2.7 

TB fluorospcopy 1.0 <1-1.0 

Postpartum mastitis X-ray 1.1 <1-1.4 
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Table 4: Number of basal cell carcinoma claims at each currently-designated SEC site (as of 

June 5, 2007) 

SEC3 Site (and time period covered by the 

approved SEC class) 

Number of claims 

with basal cell 

carcinoma as a 

listed cancer 

Allied Chemical (1/1/59-12/31/78) 24 

Amchitka Island Nuclear Explosion Site 

(before 1/1/1974) 36 

Ames Laboratory (1/1/42-1/31/54) 6 

General Atomics (1/1/60-12/31/69) 18 

Harshaw Chemical (1/1/42-11/30/49) 0 

Iowa Ordnance Plant (3/1949-12/1974) 96 

Los Alamos National Laboratory (9/1/44-

7/18/63) 74 

Linde Ceramics Plant (10/1/1942 – 

10/31/1947) 54 

Mallinckrodt Chemical Works, Destrehan 

Street Facility (1942-1957) 82 

Monsanto (1/1/43-12/31/49) 2 

Nevada Test Site (1/27/51-12/31/62) 96 

Oak Ridge Gaseous Diffusion Plant (K-25 

Site) (before 2/1/1992) 372 

ORINS (5/15/50-12/31-63) 3 

Pacific Proving Ground (1946-1962) 19 

Paducah Gaseous Diffusion Plant (before 

2/1/1992) 481 

S-50 Thermal Diffusion Plant (7/9/44-

12/31/51) 3 

Portsmouth Gaseous Diffusion Plant 

(before 2/1/1992) 290 

Y-12 Plant (3/1943-12/31/1957) 329 

 

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 Special Exposure Cohort